IP telephony is a relatively new advancement in telecommunications technology. Over time many end-users are expected to make a transition from a traditional Public Switched Telecommunications Network (PSTN) to IP telephony networks. In the immediate future, a majority of telephone traffic will both originate and terminate on the PSTN. When providing services to such calls from the IP address space, such as, for example, call control and billing services, calls will be routed from the PSTN to the IP address space for one or more services and will be terminated in the PSTN address space.
Current methods for routing calls from the PSTN address space to the IP address space are inefficient in that they unnecessarily use more resources than required. A method for more efficiently routing calls that originate and terminate in the PSTN address space, but require one or more services in the IP address space is needed.